The invention relates to a method for joining at least two rotor elements of at least one rotor of a turbomachine in accordance with the present invention. The invention further relates to a measuring apparatus and a mounting apparatus.
A rotor of a turbomachine is composed of individual rotor elements, such as disks, drums, and/or shafts. A goal herein is to minimize during mounting any out-of-balance of the rotor to be manufactured and hence to improve its performance. This is usually accomplished by the principle of trial and error. After two rotor elements have been joined, the outcome is inspected and matched to manufacturing specifications. In the event of an adequately good outcome, the next step of mounting can occur. In the event of a poor outcome, the two rotor elements have to be taken apart again and joined to each other once again in another relative mounting alignment. Afterward, it is necessary to inspect once again whether the out-of-balance of the rotor that results therefrom meets the specifications. These steps have to be repeated until the entire rotor has been assembled and the specifications placed on the out-of-balance thereof have been met. It is therefore not possible to plan a rotor assembly and the outcome may require improvement.
For this reason, there are providers of so-called rotor optimization methods. Known in this case are, for example, methods of the companies Axiam and Precitech. In these methods, a radial runout of at least one radially outer-lying cylindrical surface of the rotor elements is detected at each of at least two points that are spaced axially apart from each other by using special tactile sensor elements. Depending on these measurement data, it is then determined how the individual rotor elements should be aligned relative to one another during mounting in order to minimize the out-of-balance of the rotor to be manufactured.
However, a drawback of this known rotor optimization method is that it is not sufficiently precise for turbomachines for which particularly high demands are placed on the out-of-balance of the rotor. Especially in the case of particularly large turbomachines and correspondingly particularly large rotor elements, the known methods are not sufficiently precise to reduce the out-of-balance to an acceptable magnitude.